gml:Conversion is a concrete operation on coordinates that does not include any change of Datum. The best-known example of a coordinate conversion is a map projection. The parameters describing coordinate conversions are defined rather than empirically derived. Note that some conversions have no parameters.This concrete complex type can be used without using a GML Application Schema that defines operation-method-specialized element names and contents, especially for methods with only one Conversion instance.The usesValue property elements are an unordered list of composition associations to the set of parameter values used by this conversion operation.
The attribute gml:id supports provision of a handle for the XML element representing a GML Object. Its use is mandatory for all GML objects. It is of XML type ID, so is constrained to be unique in the XML document within which it occurs.
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<element name="Conversion" type="gml:ConversionType" substitutionGroup="gml:AbstractGeneralConversion"><annotation><documentation>gml:Conversion is a concrete operation on coordinates that does not include any change of Datum. The best-known example of a coordinate conversion is a map projection. The parameters describing coordinate conversions are defined rather than empirically derived. Note that some conversions have no parameters. This concrete complex type can be used without using a GML Application Schema that defines operation-method-specialized element names and contents, especially for methods with only one Conversion instance. The usesValue property elements are an unordered list of composition associations to the set of parameter values used by this conversion operation.</documentation></annotation></element>